Film applicator



- March 21, 1939.

J. J. BRADLEY. JR. ET AL FILM APPLICATOR Filed July 21, 1937 PatentedMar. 21, 1939 PATENT OFFICE mar APPLICATOR John J. Bradley, In, EastWalpole, and Berton L. Seekins, Norwood, Masa, assignors to Bird & Son,Inc., East Walpole, Mass., a corporation of Massachusetts ApplicationJuly 21., 1937, Serial No. 154,808

3 Claims. .(Cl. 91-625) This invention relates to a film applicatordevice for applying to a flat surface a film of liquid or plasticmaterial,--or.dinarily a hardenable film-forming material such as dryingoil, lacquer, varnish, paint, or a plastic, though the device is usefulin applying various other sorts of films.

In several industries, particularly those engaged in the making ofprotective coatings such as paint and varnish, it is desirable andnecessary to apply coatings of such films to panels, commonly of glass,wood, or metal, for purposes of visual examination and various sorts oftesting. It is essential that the test films be of uniform and definitethickness when comparisons or studies areto be made of such films but ithas been difiicult to secure films of uniform and definite thickness bymeans of the usual method of applying paint, varnish, or the like byspraying or brushing, and then repeatedly weighing the test surfacestogether with the applied samples and from the volume and areacalculating to determine the thickness of. the liquid film applied.Thismethod is both tedious and inaccurate, inasmuch as the individualoperator varies in his technique of applying the coating and theuniformity of film over any area (even if the area be accuratelymeasured) is but approximate. Other known devices are either cumbersomeor complicated in operation and are very limitedin area of surface whichcan be coated and, more-1 over, none of these machines can applysimultaneously two or more coatings or films.

The film applicator of our invention provides a vantages willhereinafter appear from the descriptions and drawing in which Fig. 1 isan isometric view illustrating the device in use applying to a testpanel films of three sample materials; I

Fig. 2 is a front elevation of the device in place upon a test panel;and Fig. 3 is an enlarged cross-sectional view illustrating the devicein use and the mode of application of the liquid or plastic material ina uniform layer upon the test panel.

Referring to the drawing, in which like numerals represent like parts,the film applicator device, generally designated 2; in its preferredform, is made from a rectangular bar of metal and has opposite ends 4 ofrectangular form having,

therebetween, an elongated section of irregular form presentinglongitudinally extending working surfaces 6, 8 and ill, the ends ofwhich terminate at the surfaces I. As will be seen from the drawing, thedevice, in working position upon a panel i2, presents thereabove andconverging therewith a portion presenting the surface 6 followed by aportion 8 spaced from the panel l2 9. distance (see Figs. 2, and 3)approximately twice the thickness of the film it is desired to lay, theportion 8 being followed by the portion presenting the surface Idiverging rearwardly from the panel I 2 so that, as the bar is moved inthe direc- V 7 tion indicated by the arrows (Figs. 1 and 3) thefilm-forming material or mass I is pushed forward leaving behind a'filmI 6 which is formed by the bar as it is drawn along.

Referring to Fig. 1 there are shown materials, for example, of threedifierent colors simultaneously being applied to a panel l2 and, in thiscase, one of the materials, being adjacent to surface 1, has impartedthereto a straight well defined edge whereas the lines of merger andopposite edge of the three applied materials present somewhat irregularlines of demarcation. This is 5 of some advantage particularly wheredifierent tones or shades of color are to join or merge with one anotherin the finished work. If it is desired to have straight lines definingdivisions between various shades or tones, that they be accomplished byrelatively thin divisions (not shown) built into the working portion ofthe bar. The thickness of the film, in the structure as shown, is fixedby the spacing of the surface 8 from the panel l2 and that iscontrolled, in the preferred form of structure, by the extent to whichthe surface 8 is carried above (see Figs. 2 and 3) the panel-contactingportions of the end sections 4. In practice it appears preferable to ,7have a series of bars made up to apply, respectively, differentthicknesses of film though it will be obvious that a given bar can bemade adjustable, as by set screws or the like in the ends, to provide anadjustable fixed spacing of the surface 8 from the panel l2. .As abovementioned however, it is preferred to have the recesses or 1 clearanceof the surface 8, so to speak, built into the tool so that, it is alwaysfixed and thus provides a film of definite thickness, and regardless ofwhether the consistencies of the materials applied vary. The thicknessof material applied with any given tool is the same and uniform and isapproximately half of the clearance cut of the tool.

It is found in practice that the device is of par- 5 ticularadvantageland utility becauseof the uniformity produced, for example, inthe testing of the dispersion of pigment in thickness. A tool formed tolay a thin film, say .0002" to .001", will clearly show the degree offineness of the pigment.

can be used to determine whether the pigment grinding has reached acertain desired point and provides an extremely quick method so that thedegree of dispersion can be accurately esti-' mated in the wet paint,and also in comparing the degree of dispersion in pigment 0 variousvehicles. Color matching can also be acc ately done where extremeaccuracy is necessary because the variations due to comparing films ofdifferent thicknesses are eliminated as it is possible to draw films ofmore than one color or shade simultaneously, as above mentioned. It isalso found that measurements of physical, optical and chemicalcharacteristics of any film, or comparisons between different typefilms, may be more accurately made.

It is of course contemplated that the device-in use may be drawn overthe surface which is stasurfaces, including a leading surface convergingtoward the plane of the work-contacting portions and a rear surfacemerging with said leading surface to provide a connecting surface evenlyspaced from said plane a predetermined distance to lay a liquid film ofdesired thickness. 2. A device of the class described characterize by amember providing an elongated inclined surface on the forward sidethereof adapted to confine a mass of hardenable film-forming material,an elongated inclined surface on the rearward side thereof, and a narrowelongated portion therebetween connecting said surfaces, and spacingmeans at the ends of said member adapted to fix the vertical distancebetween said portion and an opposing panel thereunder so as to providean elongated narrow filmlaying opening.

3. A device of the class vdescribed characterized by a member providingan elongated inclined surface on the forward side thereof adapted toconfine a mass of hardenable film-forming material,

an elongated inclined surface on the rearward side thereof, and a narrowelongated portion therebetween connecting said surfaces, and spacingmeans at the ends of said member adapted to fix the vertical distancebetween said portion and an opposing panel thereunder said surfaces,connecting portion, and spacing means being so related, constructed andarranged as to provide an elongated narrow film-laying opening definingapproximately twice the thickness of 1a film -laid therewith. I

JOHN J. BRADLEY, JR. BERTON L. SEEKINS.

